不同蛋白质和脂肪来源饲粮对冬毛期雌性蓝狐营养物质利用和氮代谢的影响

Effects of Different Dietary Protein and Fat Sources on Nutrient Digestibility and Nitrogen Metabolism of Female Blue Foxes during Fur Development Period

本试验旨在研究不同蛋白质和脂肪来源饲粮对冬毛期雌性蓝狐营养物质利用和氮代谢影响。选择(129±5)日龄、体重相近、健康雌性蓝狐40只,随机分成4组。试验采用双因子试验设计,设2个不同饲粮蛋白质来源(P植和P动)是植物性和动物性蛋白来源,2个不同饲粮脂肪来源(F植和F动)是豆油和猪油,组成4个处理(P植F植、P植F动、P动F植、P动F动)。在冬毛期内,进行了消化试验和氮平衡试验,分析蓝狐的粗蛋白表观消化率、粗脂肪表观消化率、氮沉积、蛋白质生物学价值等指标。结果表明,P植组蓝狐的粗蛋白、粗脂肪和总能表观消化率极显著高于P动组(P<0.01),干物质表观消化率显著高于P动组(P<0.05),但P植组氮沉积、净蛋白质利用率、蛋白质生物学价值却极显著低于P动组(P<0.01);猪油组(F动组)粗蛋白、粗脂肪和总能表观消化率低于豆油组(F植组),但猪油可以极显著降低饲粮的尿氮,提高饲粮的蛋白质生物学效价(P<0.01)。由此得出,蓝狐对植物性饲料已经适应,但蛋白质生物学价值却极显著低于动物性蛋白饲料,所以蓝狐实际生产中要想以植物性蛋白饲料为主则要考虑氨基酸平衡问题;豆油的脂肪消化率虽较高,但猪油可以提高氮利用和氮沉积,所以混合油脂生产效果会更好。

The trial was conducted to evaluate the effects of different dietary protein and fat sources on nutrient digestibility and nitrogen metabolism of female blue foxes during fur develop- ment period. The animals were randomly assigned to four treatment groups with 10 females in each group. The randomization was based on age and initial body weight. The method of double- factor design is adopted. Two dietary protein sources were plant protein and animal protein （P plant and P animal ）, two dietary fat sources were bean oil and lard （F plant and F animal）, in four kinds of experimental diets. The trials of metabolism and nitrogen balance were used to ana- lyse the digestibility of protein, digestibility of fat, nitrogen retention and protein biological value. The results showed as follows： digestibility coefficients of protein, ether extract, energy（P〈0.01） and dry mass（P〈0.05） in P plant group were significantly higher than that in P animal group, but nitrogen retention, net protein utilization and biological value of protein in P plant group were extremely significantly lower than that in P animal group（P〈0.01）; digestibility co- efficients of protein, fat and energy in F animal group （lard group） were lower than that in F plant group （bean oil group）, but lard could materially improve biological value of protein and materially reduce urinary nitrogen （P〈0. 01）. In conclusion, nutrient digestibility of dietaryplant protein source is higher, but biological value of protein is significantly lower than that of animal protein source. If feeding blue fox with plant protein mainly in practical production, it is should be considered the balance of amino acids. Fat digestibility of bean oil is higher, but lard can improve nitrogen metabolism and nitrogen retention. So the effect of production will be better when using mixed fat.